A quarter midget is a type of racecar. It is
similar to a go-kart with several major differences, the most conspicuous
being the roll cage. I have a quarter midget that I race on an oval track
every Saturday during the racing season.
In order to keep racing fair, the combined
weight of each car and driver in my class has to meet or exceed a minimum
weight requirement after the race. To make minimum combined weight, I must
add 16.3 kilograms. I can add this weight to any part of the floor pan.
How does weight distribution affect the speed of
a quarter midget?
When a car rounds a turn, it counts on its tires
and suspension to give it traction. A good test is to run a car around a
skidpad. A skidpad is a circular track. The driver has to balance speed
with control to keep the car from spinning off the road. I used my track,
which is just an elongated circle, as a skidpad. From this, a lateral g
force is calculated. G-forces are published in performance tests or car
The extra weight in my car is there to make
minimum weight for my class and has a mass of 16.3 kgs. I chose three
locations to place the weights-A, B and C. The weight is normally placed in
position A, making it the control. The 4th setup is balanced,
and the 5th setup has no weight added. Setup 6 was used as the
Note: All the tests were done on the same day
with the same chassis and engine settings.
I weighed the car using four scales so I could
calculate the percentage front and rear. I also calculated the Moment of
Inertia of the added weight. Moment of Inertia is the resistance of the car
to turning due to the placement of the weights. I=mr2
Possible errors: my performance as a driver may
have deteriorated near the end. Track conditions may also have improved due
to the rubber being added to the track. Gas was being used up, so the
weight was decreasing slowly.
Improvements: Fill with gas before every run.
Race on an indoor track with no weather conditions. Run each test a
different day so I will be equally alert for each run.
Applications: Any driver on a short, oval track
could use these results. Quarter Midget, Go-kart and quad racers could
benefit from this information. It could give someone an edge in
Weight transfer is the movement of weight to the
outside of the turn. This can cause a car to skid if there isnít enough
weight on the inside of the turn to counteract it. For this reason, I lean
to the inside of every turn.